A Question for Flat Tired Bandsaw Owners

[Bill Space]

Hi!


When I bought my 20" Davis and Wells bandsaw it had flat tires, but the previous owner was tracking the blade in the center of the wheels, which did not work well to say the least.

So I crowned the tires and the blade tracking suddenly became good, with the blade tracking on the center of the wheels.

Even though the manufacturer of this D&W bandsaw calls for crowned tires, my guess is that MAYBE I could have run the saw with flat tires, had I known at the time that flat tire bandsaws run the blades with the teeth hanging off the front of the tire.

This leads to my question:

On your flat tire bandsaws, do the blades run with equal amounts off the fronts of both tires? Or do the blades track differently on the tires? If there are differences, does the blade run with the teeth off one tire, but with the blade totally in contact with the other tire? Or???


Where is the blade positioned on your flat tires when you are happy with the setup?

This is a question driven by an interest I developed after buying the D&W.

Thanks for any experience given!

Bill

[Tom M King]

Off both equally on the Centauro 600. I've never had a small blade on that saw-only 1".

[Andrew Hughes]

On my saw the teeth hang off pretty equal. Here’s another blade position to check are the tips of the teeth square to the table. We all check the sides of the blade have you ever checked the tips.
The plot thickens with bandsaw mysteries :)
Almost forgot to mention my saw Agazzani B 20/20

[Van Huskey]

On all the saws I have and have seen they are very similar overhangs top and bottom, probably a very small difference but visually they look near identical.

[Bruce Page]

As above, the teeth run equally on my MM16.

[Edwin Santos]

The overhang is pretty much the same on top and bottom wheels on my Minimax s500P (MM20). This is typically when running a 1" Woodmaster CT blade which is my most used blade on that machine and yes, like the others, I run it with the teeth overhanging the front of the wheel.
However when running blades smaller than 3/4" on that particular saw, i.e. 1/2" or 3/8", I track in the center of the upper wheel and it works very reliably. I do find that as the blade gets smaller, they tend to track further forward of center on the lower wheel.

[Pat Barry]

My teeth run in the ribber of the flat wheels. I wouldn't think to have them run by overhanging the wheel. I kinda doubt that the thrust bearings and guides can move that far. This seems nonsensical.

[Mike Cutler]

Bill

Rikon 10-340.
Wheel rim width. 1-3/4".
Tire width. 1-1/2".
Blade width. 1" ( Lennox 2/3 Varipitch TrMaster.)
Front of tooth to edge of tire:
1/8 inch for top wheel.
3/16 inch for bottom wheel.
Blade is perpendicular to table in all directions.

The gullets on the TriMaster blade are quite deep. The blade, while being 1" wide front of tooth to back, is probably about 5/8" thick from the deepest part of the gullet to the back. The gullets on a TrMaster blade are not the same dimension, tooth to tooth.

This bandsaw bug has bitten you hard my friend. No worries though, I understand completely.
I'm not quite the bandsaw aficionado Van Huskey is, only because I don't have the space, but the bandsaw is, and always has been, my favorite wood working machine since i was tall enough to use one.
I have two table saws and both of them would go before my band saws. A table saw is easily replaced with other techniques and tools. No other machine can do what a band saw does. ;)

[Bill Space]

Interesting information.

Looks like you flat tire bandsaw guys may experience less variability than the crowned tire guys.

It seems like flat tired bandsaws are mostly larger, higher end machines. Perhaps the build quality is reflected in what seems to be your consistent blade position/tracking.

Thanks for the feedback. Much appreciated!

[Bill Rhodus]

I have a saw in my shop that I run one inch bands on steel wheels (no tires) and the saw hangs off the front about the same for both wheels. this is the same approach used in the mill where I worked; saws up to 8" wide ran on flat wheels. My other saws run narrower bands on crowned, tired wheels and this approach appears to work well on narrow saws.

[Van Huskey]

My teeth run in the ribber of the flat wheels. I wouldn't think to have them run by overhanging the wheel. I kinda doubt that the thrust bearings and guides can move that far. This seems nonsensical.

Are you suggesting we all believe in fairies? Teeth off the front of the tire is just how most flat tired saws are designed to run. Otherwise, the teeth will chew up the tire, at some width thinner blades have to be run near the center of the tire usually that is about the 1/4" band area.

BTW what saw do you have?

[peter gagliardi]

Why do flat tired saws have their wheels chewed off if the blade rides back into the rubber, but the crowned tire saws do not? :confused:
IF the flat tire saws run better with teeth off the front, it is only because the set of the teeth change the blade dimension, and therefor the running dynamics over the flat wheel.
No blades should chew a tire, unless you are using the saw wrong.

[Van Huskey]

Why do flat tired saws have their wheels chewed off if the blade rides back into the rubber, but the crowned tire saws do not? :confused:
IF the flat tire saws run better with teeth off the front, it is only because the set of the teeth change the blade dimension, and therefor the running dynamics over the flat wheel.
No blades should chew a tire, unless you are using the saw wrong.

First, only set tooth blades change the blade dimensions, due to the manufacturing process of the set they are slightly shorter on the tooth side of the blade making them want to ride forward compared to a blade with no set.

I assume your thought process is that if the blade doesn't slide on the tire it can't cut into it. However, especially with carbide teeth, the constant pressing in and out of the side of the tooth acts as a die and cuts into the tire. Over time this will cause chunks to pop out. The worst case I ever saw was on a used Agazzani where it literally had a groove chunked out of it where the teeth had been riding, the owner never knew to move the blade forward and just tracked the blade where he had on his previous saw. The Agazzani has vulcanized tires so the durometer might be higher which MAY exacerbate the issue. Blades with set teeth aren't as bad. The difference for a crowned tire is the teeth either don't touch the tire at all or they have lower pressure when they do.

If you need a painful demonstration take a sharp circular saw blade and press it sideways really hard into your thigh. You could even see the difference between a high ATB blade and a triple chip grind so similar to the difference between a Resaw King and Trimaster. Theoretically, the RK will cause more tire damage than a Trimaster.

[Bill Space]

Edwin,

That is interesting. It seems to concur with others inasmuch that when running narrower blades on flat tire wheels they seem to move the tracking fully onto the tires...

My take on it anyway.

Bill

[Bill Space]

Pat,

As as I mentioned, when I bought the D&W 20” saw I did not realize flat tire bandsaws generally run their blades off the front of the tire.

The reason is that the overhang on the front of the wheel works the same on the blade as the crown does on a crowned tire.

BUT whatever works for you is not the debate here! Thanks for sharing your experience!

Bill

[Bill Space]

Bill

This bandsaw bug has bitten you hard my friend. No worries though, I understand completely.
I'm not quite the bandsaw aficionado Van Huskey is..


HA HA HA! You got me!

After buying the Davis & Wells bandsaw and realizing that I did not know much about bandsaws (other than they cut wood well), I decided to learn something, or try to. I think I have been progressing. But you sure called me out for when I am!

[Bill Space]

Are you suggesting we all believe in fairies? Teeth off the front of the tire is just how most flat tired saws are designed to run. Otherwise, the teeth will chew up the tire, at some width thinner blades have to be run near the center of the tire usually that is about the 1/4" band area.

BTW what saw do you have?

Just to add to Van’s comment, I believe it is pretty much accepted that when a blade overhangs the front of the tire, the effect of that overhang is similar to what a blade sees when running on a crowned tire.

So the short of the story is that on flat tire bandsaws they get blade stability from the point of overhang, in a fashion similar to how a crowned tire bandsaw gets blade stability from the effect the crown has on the blade.

But this difference was not the the purpose of this thread.

I was really just curious as to how blades generally tracked on flat wheels. I regret at the time I did not realize the difference between flat and crowned tires and crowned my tires without experimenting.

[Bill Space]

Why do flat tired saws have their wheels chewed off if the blade rides back into the rubber, but the crowned tire saws do not? :confused:
IF the flat tire saws run better with teeth off the front, it is only because the set of the teeth change the blade dimension, and therefor the running dynamics over the flat wheel.
No blades should chew a tire, unless you are using the saw wrong.


Peter,

Van addressed you post with specifics and I will defer to him as I am a learner.

BUT I would guess that if a flat tire bandsaw has its tires chewed off, that it is because it has not been set up to run as designed.

By design, a flat tired bandsaw should run with the blade overhanging the front of the tire. In most cases, except for possibly the highest TPI blade, this should put the teeth off the rubber. So no chewing of the rubber should occur.

I think most would would agree with you: “No blades should chew a tire, unless you are using the saw wrong.”

[David Kumm]

I would only add that I would not equate flat tires to high end saws. Vertical bandsaws of the size used in wood shops ( 20-36" ) using blades in the 1" range run flat tires for ease of changing, not because they are better than crowned. Crowned tires are a pain to swap and crowning them is usually beyond the ability of a hobby or even a commercial shop guy. I have to pull mine off and take them to a shop. I equate it to machines using sealed bearings. It is not about making machines better ( sealed bearings in many applications are an inferior option ) but making them easier to maintain. Both sealed bearings and flat tires may need to be replaced more often, but they require less skill and cost when it is needed. Dave

[Edwin Santos]

Edwin,

That is interesting. It seems to concur with others inasmuch that when running narrower blades on flat tire wheels they seem to move the tracking fully onto the tires...

My take on it anyway.

Bill
Bill,
Well after reading Van Huskey's post above, I don't want to chew my rubber tires up, so maybe I should be tracking my 1/2" and 3/8" bands with the teeth off the upper wheel. I don't often run narrower blades on the MM20/s500P but when I have a moment, I'll try tracking a narrower blade both ways and see what happens.

Or if I keep living dangerously and tracking the narrower blades in the center, I can keep an eye on the tires for signs of "chewing".
Not that I would step out on a high wire and disagree with Van on the subject of bandsaws, but in my simpleton mind, the tire is rubber because rubber has the property of give and spring back. I can more easily visualize the die cutting action Van mentions on an older tire that has become dried out or brittle. Or maybe in a situation where way excessive tension is being applied. Or maybe the saw left under excessive tension for months unused where the tooth pattern is left to emboss itself into the tire.
But in the absence of those conditions, I would have to see the phenomenon to believe that teeth can laterally cut the bandsaw tire.
Edwin

[Van Huskey]

Edwin, don't think anything of disagreeing with me, I am on a learning arc like everyone else. Dave corrects me often and he knows a lot more about old iron saws than I do.

Rubber is indeed resilient and the durometer impacts how quickly this happens. While I can't show you I can give an idea about what to consider. First, keep in mind the teeth are rolling into the wheel hundreds of times a minute. Also, think about the action of the tooth edge as the tire rolls into it so that the leading edge of the tooth is pressing into the rubber under pretty high pressure. The grind of the teeth will also affect how quickly damage occurs. A blade like a Resaw King with high shear faces is likely to cause quicker damage than the triple chip grind of a Trimaster. Think about pressing the side of a blade into the rubber with a couple of hundred pounds of pressure 5 or so times a second. Now understand I have not created this damage myself. It has been mentioned by Erik and Sam in the past and I have seen the results which the only logical explanation was damage caused by teeth. I run 1/4" blades back on the tires but I have seen no damage from them, but they are set teeth not ground, run at lower tension and they are rarely on my flat tired saws.

[peter gagliardi]

Van, what you suggest, may well be true. However, it does not compare with my experiences, over the last 32 years in my own small pro shop.
I have had many bandsaws, and never experienced those effects. Just sold my 36” Tanny last year, after owning it for 20 years with moderate use. I put new tires on it when I got it. Always ran every kind of bandsaw blade on it in the center of the crown. Steel and carbide.
Lots of hours and miles of sawing.
Tires nearly perfect when it left.
I now have a Y-30, and a Y-36. The 30 I put new tires on about 8-10 years ago, and the 36, needs them as the final on my restoration.

In my opinion, Proper care and use, setup and tension, along with PROPER dust collection, and most if not everyone on this forum would never wear out a new set of tires.

Poor maintenance, combined with poor operation will do much more harm to tires than the actual position they sit at in my opinion that is backed by some experience. I certainly don’t know it all myself, but I do understand what works on my machines.
Perhaps the rubber compounds used on some of these machines is not optimal.

[Van Huskey]

Always ran every kind of bandsaw blade on it in the center of the crown.

The discussion is primarily about flat tires. Rereading your post I may have misunderstood your point. Running the teeth on a flat tire is using it incorrectly (save narrow blades which you have no choice but to track them back on the tire). If that was your point then I agree. Obviously crowned tires like you have on your saws left the teeth up to either clear or at least significantly reduce the touching of the teeth to the tire.

"Why do flat tired saws have their wheels chewed off if the blade rides back into the rubber, but the crowned tire saws do not? "

I am kinda confused about the exact meaning of this question from your first post and read it like I I figured you meant it. I replaced wheels chewed off with tires chewed off and blade rides back with teeth ride back. Honestly, this seems self-explanatory to me, the teeth are lifted by the crown but flat tires have nothing to lift them clear of the tire.

All the saws you listed are designed for crowned tires, though they are generally relatively low crowns compared to smaller saws. Unless you ran them without crowning the tires they aren't germane to the discussion.

[Randall J Cox]

I have an 18" S45 MiniMax running a lennox die master II 1/2" blade and teeth hang off the rubber of the top tire but run in the middle of the bottom tire. Been running it that way for a couple of years, bottom tire looks fine. Seems to track fine also. Randy

[peter gagliardi]

I understand what you are saying, but just because the saws I reference run a crown, doesn’t necessarily take them out of the discussion.
The first time I checked the “crown” I thought they were flat.
What I came to understand is that “crown” is sometimes measured in thousanths of an inch across a tire.
My Tanny had effectively only about .030” across the 2” wide tire. Add the proper tension, and the tire is almost effectively flat at the top and bottoms of the wheels, as it compresses slightly- certainly not enough to keep the set of teeth from contacting the rubber.

Crown comes into play, and does it’s job almost completely at a point level to the axles- biggest part of the tire “grabs” the blade and keeps it tracking.

Not being argumentative, just offering more info to the discussion.

I have run smaller saws that did have flat wheels, but the setup,and tracking in my case was always the same. Center of wheel as much as possible.

Essentially, unless the compound on flat tired saws is vastly different than crowned, It should make no difference whether teeth are on or off the tire in regards to WEAR.
If however, you run heavy set on the teeth- effectively creating the same idea of crown, but with the bandsaw blade being the dimensionally changing dynamic vs the crowned tire.

The exception I have seen are the industrial powerfed resaws that run flat steel wheels. They run teeth hanging off the front- set teeth contacting steel wheels is not a good combo.

[Van Huskey]

I understand what you are saying, but just because the saws I reference run a crown, doesn’t necessarily take them out of the discussion.
The first time I checked the “crown” I thought they were flat.
What I came to understand is that “crown” is sometimes measured in thousanths of an inch across a tire.
My Tanny had effectively only about .030” across the 2” wide tire. Add the proper tension, and the tire is almost effectively flat at the top and bottoms of the wheels, as it compresses slightly- certainly not enough to keep the set of teeth from contacting the rubber.

Crown comes into play, and does it’s job almost completely at a point level to the axles- biggest part of the tire “grabs” the blade and keeps it tracking.

Not being argumentative, just offering more info to the discussion.

I have run smaller saws that did have flat wheels, but the setup,and tracking in my case was always the same. Center of wheel as much as possible.

Essentially, unless the compound on flat tired saws is vastly different than crowned, It should make no difference whether teeth are on or off the tire in regards to WEAR.
If however, you run heavy set on the teeth- effectively creating the same idea of crown, but with the bandsaw blade being the dimensionally changing dynamic vs the crowned tire.

The exception I have seen are the industrial powerfed resaws that run flat steel wheels. They run teeth hanging off the front- set teeth contacting steel wheels is not a good combo.

I'm with you now and understand what you are saying. As for the compound and characteristics of the various tires, all I can say is they vary quite a bit. The Agazzani with the grooved tires were vulcanized and normally outlast other tires by a good margin which is a good thing since they had to be sent back for replacement. This process may have made them more susceptible to tooth damage despite being more durable otherwise. Erik and Sam (former and current sales people) have both mentioned the issue and have been hands-on with hundreds of flat tired saws, Sam doesn't visit anymore and Erik is out of the biz and visits rarely. I have to talk to Sam fairly soon to get some quotes on saws for my new shop and will ask him about the issue. It is somewhat of a non-issue since running blades centered on the wheel is incorrect on these saws.

[Edwin Santos]

Edwin, don't think anything of disagreeing with me, I am on a learning arc like everyone else. Dave corrects me often and he knows a lot more about old iron saws than I do.

Rubber is indeed resilient and the durometer impacts how quickly this happens. While I can't show you I can give an idea about what to consider. First, keep in mind the teeth are rolling into the wheel hundreds of times a minute. Also, think about the action of the tooth edge as the tire rolls into it so that the leading edge of the tooth is pressing into the rubber under pretty high pressure. The grind of the teeth will also affect how quickly damage occurs. A blade like a Resaw King with high shear faces is likely to cause quicker damage than the triple chip grind of a Trimaster. Think about pressing the side of a blade into the rubber with a couple of hundred pounds of pressure 5 or so times a second. Now understand I have not created this damage myself. It has been mentioned by Erik and Sam in the past and I have seen the results which the only logical explanation was damage caused by teeth. I run 1/4" blades back on the tires but I have seen no damage from them, but they are set teeth not ground, run at lower tension and they are rarely on my flat tired saws.

Van, just because I cannot easily visualize something doesn't mean it isn't correct. When I'm back from traveling, I'll have to experiment a little with this.

I do recall Sam telling me that the saw is set up at the factory so that if you track a 1" blade with the teeth just overhanging the wheel, it should be in the same position on the lower wheel, but as you go to smaller bands, they will track forward on the lower wheel when compared to the position on the upper wheel. I just assumed that this might be part of the reason to track a narrower band in the center on the top wheel, the assumption being that overhanging the top tire would run the band right off the lower one. But as I say, I haven't tried it. I'll report back when I do.

Thanks for the additional explanation,

[Joe Calhoon]

I have never run blades hanging over the edge of the wheel. But reading through this not sure now if I have crowned tires or flat. My 36 Agazzani and 20” Hema have what appear to be flat wheels but putting a ruler on them they taper off just slightly. My 14” Delta a little more. And I recall that a 20” Delta I had was very crowned.

My rubber is are all in good shape, the Agazzani I bought new and have done a lot of resawing with it using mostly bimetal 1” and 1 1/4 blades. The Hema was used but the rubber is in good condition. The Hema actually has a sign inside saying to run blades to the center of wheel.

[Erik Loza]

Merry late Christmas, gang. On the Italian bandsaws, here is how they break out...

-True-flat tires: Centauro (aka Minimax MM16/20/24/S400/500/600/et al), ACM, and (I assume) Felder.

-“Slightly crowned” tires: Agazzani, Minimax S45 and S45N (which are actually made by Minimax rather than Centauro), Meber, and all the ancient ones like Sagittario.

I cannot remember what Stomana of Bulgaria’s tires looked like. That was Laguna’s budget LT series for a while. Regarding tire design, this is one of the last things the various engineers spend any time on. We like to analyze this or that about the Euro bandsaws and from the sales side of things and it’s used for marketing here but a bandsaw is one of the least engineered machines from a European perspective. In fact, I would be willing to bet that if you asked one of they why they used a truly flat tire versus a slightly crowned tire, the answer would be some combination of, “Because that’s why we’ve always done it” and “It’s the most economical way”. Just like if you were to ask any of the mass-producers of Asian budget bandsaws why all their tires are crowned, they would probably say, “Aren’t they all that way?”.

Erik

[Edwin Santos]

Merry late Christmas, gang. On the Italian bandsaws, here is how they break out...

-True-flat tires: Centauro (aka Minimax MM16/20/24/S400/500/600/et al), ACM, and (I assume) Felder.

-“Slightly crowned” tires: Agazzani, Minimax S45 and S45N (which are actually made by Minimax rather than Centauro), Meber, and all the ancient ones like Sagittario.

I cannot remember what Stomana of Bulgaria’s tires looked like. That was Laguna’s budget LT series for a while. Regarding tire design, this is one of the last things the various engineers spend any time on. We like to analyze this or that about the Euro bandsaws and from the sales side of things and it’s used for marketing here but a bandsaw is one of the least engineered machines from a European perspective. In fact, I would be willing to bet that if you asked one of they why they used a truly flat tire versus a slightly crowned tire, the answer would be some combination of, “Because that’s why we’ve always done it” and “It’s the most economical way”. Just like if you were to ask any of the mass-producers of Asian budget bandsaws why all their tires are crowned, they would probably say, “Aren’t they all that way?”.

Erik

Erik - Would you comment on the question of running bands narrower than 1" in the center of the tire versus teeth overhanging the edge? One of the sub-questions in this thread is the risk of chewing up the tire when running a band in the center where where the teeth in the field of the tire.

Changing subjects, from your comment, it sounds like we might be over thinking and over discussing these machines in the eyes of the Italian manufacturers, and maybe we would give them a good laugh.
Thanks,
Edwin

[Van Huskey]

Changing subjects, from your comment, it sounds like we might be over thinking and over discussing these machines in the eyes of the Italian manufacturers, and maybe we would give them a good laugh.
Thanks,
Edwin

We can always take hear in the fact the guy that wrote his master's thesis on bandsaw tracking spent a whole lot more time thinking about it!

[Erik Loza]

Erik - Would you comment on the question of running bands narrower than 1" in the center of the tire versus teeth overhanging the edge? One of the sub-questions in this thread is the risk of chewing up the tire when running a band in the center where where the teeth in the field of the tire.

My rule of thumb with flat/basically flat bandsaws is that if the blade is wider than 1/2”, hang the teeth off the front edge of the tire. This is only for tire life. A 1” skip-tooth blade will shred the tire if you run it in the middle of the wheel. A 1/2” or 1/4” blade, even though it might have alternating teeth, does not have enough kerf to really hurt the tire. One exception could be the blades like Lenox Tri-master or Resaw King (though I have never personally used that blade), where the teeth are brazed on but flat in kerf. I still track those off the front of the wheel but they “probably” would not chew up a tire like a regular blade would.

On the narrower blades, I run them in the center for the reason that thin blades on tall-resaw machines have a tendency to tug much more with the cut and possibly move more on the wheel.

One note and just my personal opinion. If you own a tall-resaw Euro machines larger than 16”/400mm or so and need to use a 1/4” blade on the regular, just get a 14” bandsaw and keep it set up for that. Save the Euro machine for big blades. Due to the huge span between the wheels on something like an MM20, it is REALLY tricky to get the tension just right with thin blades. Same reason you would own a router table as well as a shaper. Just my 2-cents.

Erik